/Engine/Plugins/FX/Niagara/Source/Niagara/Public/NiagaraComponent.h
Gets the delta value which is used when seeking from the current age, to the desired age. This is only relevant when using the DesiredAge age update mode.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category=Niagara, Meta=(DisplayName="Get Desired Age Seek Delta")) float GetSeekDelta() const